It is blue-chip/red-chip time here at NFL.com, which means ranking the top players and head coaches in the NFL.

In last year's blue-chip/red-chip column, I broke it down by team. This year I'm breaking it down by positions because it keeps the number of players on the list to the select few that meet the criteria for the grading system.

Blue chips and red chips: Defense

Michael Lombardi ranks the best players at each position, handing them his blue- and red-chip ratings. Take a look at the best in the game at the defensive spots.
More ...

With a great deal of help from NFL Network colleague Brian Baldinger, we built a blue-chip/red-chip board. The goal was to get a top 10 at each position. But at some spots, like wide receiver and cornerback, we went more than 10. At others, like center, we went less. The end result is the top 73 players on offense and the top 75 on defense. Baldinger provided great insight and was a tremendous help, but I take full responsibility for the final product.

***

Definition of a blue-chip player » Player demonstrates rare abilities and can create mismatches that have an obvious impact on the game » Is a premier player in the league and a weapon on the field » Combines competitiveness and skill to have a consistent championship-level performance » Rates in the top five at his position in the league

Definition of a red-chip player » Player has abilities that can create mismatches vs. most opponents in the league » Is a featured player on the team and has impact on the outcome of the game » Player can't be taken out of the game in one-on-one matchup » Has a consistent level of performance each week » Plays at a championship level performance » Rates in the top 10 at his position in the league

***

Before you rip the rankings, make sure to read the above definitions and make sure the player you feel has been slighted fits the description. Not everyone can make the list, so there are going to be some good -- but not great -- players that fall short. In a separate column before the season, I will rank all the teams, using a point-based system, to come up with my blue-chip/red-chip power rankings.

Notes » This is the only position I had six blue-chip players. All of them are clearly vital to their teams. » I left Tony Romo off the red-chip list based on last year's shoulder injury, which affected his season. If healthy, Romo belongs on the list. » Michael Vick is not a blue-chip player yet. He needs to play an entire season the way he played last year, then he might be able to unseat someone. However, even if he does play that well consistently, I'm not sure he is better than the six players ranked higher than him.

Notes » Dwayne Bowe of the Chiefs was the hardest omission. He had 15 touchdowns last season, but it never felt like he could take over a game. » Why did 15 WRs make the cut? With all the three-receiver sets in the league, I didn't want to shortchange the position.

Notes » Both Clark and Gates have been hurt, but when they are on the field they dominate and are impossible to take out of the game. » Finley is really a blue-chip player, but due to his injury last year, I moved him down. » Rob Gronkowski of the Patriots almost made the list. With one more season like last year, he is a slam dunk to be a red chip. » Heath Miller of the Steelers is so good in pass protections and run blocking that even though he is not a down-the-field receiver, he does so many things well that he cannot be taken off the list.

Notes » It's no coincidence all 10 play left tackle; it's where the best linemen play. » Debated between Roos and McNeill for the final blue-chip spot, but ultimately settled on the Charger. Both are excellent players.